Apparatus for detecting symbol in SDM system and method thereof

Abstract

An apparatus for detecting a symbol in a space division multiplexing system and a method thereof are disclosed. The apparatus includes: a QR decomposing unit for performing a QR decomposition on a channel matrix H to decompose the channel matrix H to a Q matrix and a R matrix; a first symbol detecting unit for detecting a first symbol from a receive signal vector by using the result of the QR decomposition; a candidate symbol deciding unit for deciding the detected first symbol and Nc−1 symbols adjacent to the detected first symbol on a constellation as candidate symbols, wherein the Nc is an positive integer number; a candidate vector detecting unit for detecting Nc candidate transmit symbol vectors from the detected Nc candidate symbols; and a transmit symbol vector deciding unit for deciding an optimized transmit symbol vector among the detected Nc candidate transmit symbol vectors.

Description

FIELD OF THE INVENTION [0001] The present invention relates to an apparatus for detecting a symbol and a method thereof and, more particularly, to an apparatus for rapidly and precisely detecting a symbol in a receiver of a space division multiplexing (SDM) system. DESCRIPTION OF RELATED ARTS [0002] A wireless communication service is transited from a low speed voice communication service to a high speed multimedia communication service. Accordingly, there is a growing interest in a high speed data communication service and there are many studies in progress for increasing data transmission rate. A space division multiplexing (SDM) scheme was introduced by G. J. Foschini in 1996. The SDM scheme dramatically increases the data transmission rate by using a multiple transmit / receive antennas. The SDM scheme may be called as a bell-labs layered space-time (BLAST). The SDM scheme splits a single user's data stream into multiple sub-streams and simultaneously transmits the multiple sub-st...

AI Technical Summary

Benefits of technology

[0011] It is, therefore, an object of the present invention to provide an apparatus for detecting a symbol in a SDM system to improve a total system performance by lowering an error probability of a first detected symbol in a receiver of a space division multiplexing (SDM) system, and a method thereof.

Problems solved by technology

However, a performance of the SQRD based algorithm may be degraded compared to a conventional ordered successive detection (OSD) algorithm because a detection order of the SQRD based algorithm is not always optimized while the OSD algorithm always provides optimized detection order.

Especially, if an error is occurred from the first detected signal, the error is propagated while detecting following symbols.

Therefore, the total system performance can be seriously degraded.

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